U.S. companies that have expressed the most fervent public support for President Barack Obama’s environmental agenda are also funding its biggest enemies -- the scores of U.S. lawmakers who are climate-change skeptics and oppose regulation to combat it, according to a Reuters review of public records.

Ahead of the Nov. 8 presidential and congressional elections, the donations from companies including PepsiCo, DuPont and Google reveal a disconnect between how these companies present themselves to the public on environmental issues, and how they manage their political contributions to support business-friendly policy.

Portugal has shown that in terms of electricity at least, the answer is yes. For 107 hours in May 2016 the sun, wind and rain powered a nation.

It's not just big energy companies that are boosting the green energy infrastructure. Portugal's first renewable energy cooperative has also been busy. Starting in December 2013 with just 16 members, Coopérnico has just installed its seventh photovoltaic facility on the roof of the Irene Rolo foundation, in Tavira on the south coast of Portugal.

As the presidential election builds to a crescendo, extreme weather has brought climate change as an electoral issue into focus. Florida is facing its first hurricane landfall in a decade, resulting in the National Weather Service issuing its first-ever storm surge warning. At the same time, Louisianans are just beginning to clean up the damage from deadly August floods.

In a political season dominated by proposals for mass deportation and religious immigration bans, this is one of the few issues that has followed the predictable polarized path. Donald Trump says he’s “not a big believer in man-made climate change,” and that “there could be some impact, but I don’t believe it’s a devastating impact.” Hillary Clinton reflects the view of those who have most studied the issue, saying climate change is an urgent threat.

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Geoffrey Heal, an economist at Columbia Business School, recently published a National Bureau of Economic Research working paper that asks what it would take -- over the next 35 years -- to cut U.S. greenhouse gas emissions to 80 percent below their 2005 level. That’s not a made-up target: It’s the goal the Obama administration submitted to the U.N. It’s also the long-term goal the U.S. will bring to G20 negotiations next week. And it shows up in the 2016 Democratic Party Platform upon which Hillary Clinton is running for president. (Republican candidate Donald Trump has rejected the science of global warming. Libertarian candidate Gary Johnson recognizes climate change and is “open to” a carbon tax.)

Heal’s main goal is to figure out, in a policy-agnostic, nonpolitical way, the economics of replacing 66 percent of U.S. energy output -- the coal and gas used for electricity generation -- with renewable energy or a combination of renewables and nuclear power. “I wanted a way of doing it that was transparent,” Heal said, “in which anybody who was interested in it can understand, and, if they disagreed, they can go back and do it their own way.”